I've started working through Advent of Code 2020 while trying to learn Clojure, and I've just noticed that the challenges aren't being displayed in numerical order. The story doesn't make any sense if I follow them top-to-bottom (planes landing before they've taken off etc.), but can anyone who's already completed them tell whether they've been re-ordered in terms of difficulty? Or has something just gone a bit haywire?

I believe it is to support the story, a problem is aligned with position on the map. The hero is traveling all over the world and challenges are not aligned. In general problems are not ordered by complexity, you can try to figure out complexity by looking at leaderboard for each day to see how long it took to solve them for competitive people https://adventofcode.com/2020/leaderboard/day/9 . But this will not tell how hard it would be for you, if you are not into competitive programming

Ah, I see, I hadn't even realised that was a map! That makes sense now, thank you!

In general it does tend to be harder in the later days, but that also may vary wildly depending on where your hobbies/skills lie. Some are efficiency problems others are math oriented, others are just complicated logic, its a really mixed bag, which is what makes it awesome

So day 10 might be 3 times harder for you than day 11, but it could be the easiest for someone else because they reading about binary trees recently

Good luck!

It started to get too hard for me at day 14 iirc. At day 17 I had to drop out and become a spectator, b/c it took too much of my time. I had wonderfully fun all the 25 days, much thanks to this channel.

2020 was a little easier to skip a day or a part2, so i made it pretty far with some skips. it did get hard at times.

there were times it felt like it was built to be solved functionally with list structures.